Investment Securities - Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	$ 0	$ 6
Gross Unrealized Losses	743,159	811,136
Fair Value	4,848,607	4,843,487
Debt Securities, Available-for-sale, Amortized Cost, Total	5,591,766	5,654,617
Agency residential MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	396,895	442,996
Fair Value	2,249,080	2,242,042
Debt Securities, Available-for-sale, Amortized Cost, Total	2,645,975	2,685,038
Agency commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	53,799	61,886
Fair Value	491,681	487,606
Debt Securities, Available-for-sale, Amortized Cost, Total	545,480	549,492
Agency residential CMOs
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	53,621	60,111
Fair Value	455,682	457,063
Debt Securities, Available-for-sale, Amortized Cost, Total	509,303	517,174
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	85,772	101,075
Fair Value	685,436	670,070
Debt Securities, Available-for-sale, Amortized Cost, Total	771,208	771,145
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	50,070	60,398
Fair Value	345,639	339,326
Debt Securities, Available-for-sale, Amortized Cost, Total	395,709	399,724
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	6,172	6,898
Fair Value	102,994	102,261
Debt Securities, Available-for-sale, Amortized Cost, Total	109,166	109,159
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	6
Gross Unrealized Losses	54,953	32,868
Fair Value	289,794	311,905
Debt Securities, Available-for-sale, Amortized Cost, Total	344,747	344,767
Private label commercial MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	1,796	2,076
Fair Value	25,535	26,827
Debt Securities, Available-for-sale, Amortized Cost, Total	27,331	28,903
SBA securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	989	1,274
Fair Value	15,906	17,250
Debt Securities, Available-for-sale, Amortized Cost, Total	16,895	18,524
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	38,685	40,399
Fair Value	164,403	166,724
Debt Securities, Available-for-sale, Amortized Cost, Total	203,088	207,123
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	0	0
Gross Unrealized Losses	407	1,155
Fair Value	22,457	22,413
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 22,864	$ 23,568

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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